Whenever enemy Monkey, Tracer, Genji, Hammond, etc are diving my backline and wrecking havoc, I switch to Brigitte straight up countering their sorry asses back to spawn. I also play her as my best flex support whenever there double barriers on the enemy team coz my Lucio/Zen damage won't go through. As far as her low self healing and survivablitiy goes, you just gotta accept that and play behind cover, asking for healing from your main healer so many times. I know it is a bit difficult to use her primary fire, more than it was before, but in reality you don't really need to. You are a healer now, use your Whip Shot to trigger passive every 4-5 seconds and just heal with Repair Packs, no need to think about "getting kills", just heal. That is the key to new Brigitte.
Aside from all that, she is literally my favorite character in the game. Her voice, her personality, her innocence and strength, everything about her speaks to me. I love her and will never abandon her no matter a million nerfs come her way.